Websites that use the Secure Sockets Layer protocol (SSL) such as banking sites and online stores will have "https" at the start of their address. If Firefox can't access a secure site, it will show an error page saying:

An error occurred during a connection to (site name). Can't connect securely because the SSL protocol has been disabled. (Error code: ssl_error_ssl_disabled)

This article will describe how to enable SSL in Firefox if you get this message.

Table of Contents

Check your SSL settings

At the top of the Firefox window, click on the Firefox button and then select Options.At the top of the Firefox window, click on the Tools menu and then select Options.On the menu bar, click on the Firefox menu and select Preferences....At the top of the Firefox window, click on the Edit menu and select Preferences.

Click the menu button
and choose Options.Preferences.

Select the Advanced panel.

Click the Encryption tab.

Verify that Use SSL 3.0 and Use TLS 1.0 are check marked.

If both boxes are check marked, this section does not apply. You can skip to the next section.

If both Use SSL 3.0 and Use TLS 1.0 are not check marked, check mark both of them.

Click OK to close the Options window.Click Close to close the Preferences window.Close the Preferences window.Close the about:preferences page. Any changes you've made will automatically be saved.

The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise! to continue to the about:config page.

Type security.enable in the Search field.

If both security.enable_ssl3 and security.enable_tls are set to true, skip to the next section.

If both security.enable_ssl3 and security.enable_tls are set to false, double-click each of them to set it to true.

Try to access a secure site again. If it still doesn't work, continue in the next section.

Check your proxy settings

Some computers are configured to access the Internet through a proxy.

At the top of the Firefox window, click on the Firefox button and then select Options.At the top of the Firefox window, click on the Tools menu and then select Options.On the menu bar, click on the Firefox menu and select Preferences....At the top of the Firefox window, click on the Edit menu and select Preferences.

Click the menu button
and choose Options.Preferences.

Select the Advanced panel.

Click the Network tab.

Click Settings….

If Manual proxy configuration: is selected, you are using a manually configured proxy server. Verify that all protocols listed in the dialog box are pointing to the address of your proxy server. Contact your network administrator if you don't know this address.

If Manual proxy configuration: is not selected, this section does not apply. You can skip to the next section.

Make any changes, and click OK to close the Connection Settings window.

Click OK to close the Options window.Click Close to close the Preferences window.Close the Preferences window.Close the about:preferences page. Any changes you've made will automatically be saved.

Try to access a secure site again. If it still doesn't work, continue in the next section.